Microsoft Word includes tools that allow you to lock or unlock a document to protect it from unauthorised changes. You can lock a file by password-protecting it. A locked file cannot be opened without the correct password, so it's important to use a password you won't forget. You can also lock a subdocument, field and form in Microsoft Word, so they cannot be modified, and then unlock them when you are ready to make updates.
Go to Microsoft Word and open the password-protected file you want to unlock. You will be prompted to enter your password.
Unlock the file by re-saving the file without password-protection. Click on "File" and "Save As." Then choose "Tools" from the top area of the "Save As" dialogue box.
Select "Security Options" and remove the password from "Password to Open" and "Password to Modify" text boxes. Click "OK" to close the "Security" dialogue box.
Press "Save" to re-save the document. The file will be unlocked.
Open the master document that contains your subdocuments in Word.
Select "View" and "Outline" from the toolbar, so you can manage the subdocuments. The "Outlining" toolbar will appear.
Expand the subdocuments by clicking on the "Expand Subdocuments" button in the "Outlining" toolbar.
Go to the subdocument you wish to unlock and select the "Lock Document" button from the toolbar to unlock it.
Open the document that contains the locked field.
Place your cursor on the field you want to unlock.
Press the "Ctrl+SHIFT+F11" keys on your keyboard to unlock the field.
Open your document containing the locked form in Word.
Open the "Forms" toolbar ("View," "Toolbars" and "Customise"). Choose the "Toolbars" tab and check "Forms." Then press "Close."
Unlock the form by selecting it on your page. Click on the "Protect Form" button in the "Forms" toolbar. To make the "Protect Form" button visible, click on the arrow beside the toolbar and expand it. Then choose "Add or Remove Buttons," "Forms" and "Protect Form."